KR102087879B1 - Gear module having internal gear with 2 point contact - Google Patents

Abstract

The present invention relates to a gear module having a two-point contact internal gear, and more particularly, to a gear module applicable to a reducer. In the present invention, a gear module including a circumferential gear in which a plurality of teeth are formed on an outer circumferential surface, an eccentric rotation capable, and a plurality of grooves are formed in an inner circumferential surface and pins in contact with the circumferential gear for each groove are disposed, The pin is contacted at two contact points, and the groove has a first radius of curvature greater than the radius of curvature of the pin and a first arc of a first arc contacting any one contact point, and a second radius of curvature greater than the radius of curvature of the pin. The second part of the second circular arc made of a second arc contacting the other contact point is formed by depression, and the first radius of curvature and the second radius of curvature are respectively connected to the contact point after passing through the center point of the pin. A gear module having the same size is provided.

Description

Gear module with two-point contact internal gear {GEAR MODULE HAVING INTERNAL GEAR WITH 2 POINT CONTACT}

The present invention relates to a gear module having a two-point contact internal gear, and more particularly, to a gear module applicable to a reducer.

The reducer is a device for decelerating a high-speed rotational force input from a power device by a gear arrangement and outputting it at a low-speed rotational force, and is used in various fields.

In particular, high-precision reducers are used in fields where precise driving control is required, such as industrial robots and humanoid robots, and high-precision reducers are required to have characteristics such as high reduction ratio and repeatability.

Cycloid reducers are currently widely used high-precision reducers. The cycloid reducer has a groove formed on the inner circumferential surface, and a gear module consisting of an internal gear (12 ') with a pin (120') coupled to each groove and an external gear (11 ') engaged with the pin (120') and rotating eccentrically. As a reduction gear applied, various reduction ratios can be implemented.

At this time, the groove of the internal gear 12 'should be evenly contacted with the pin 120 in a surface contact state as shown in FIG. 1, but actually meets at one contact point due to machining and assembly tolerances. The direction of the load acting from (11 ') and the reaction force direction of the contact point can be varied. That is, the reduction gear to which the conventional gear module is applied may accelerate wear and tear due to the concentration of load and stress at one contact point, and the performance of the reduction gear may be reduced because the load direction and the reaction force direction are different.

In addition, in the conventional gear module, there is no space for lubricant to flow between the internal gear 12 'and the pin 120', making it difficult to form a lubricating film, and fine particles generated by abrasion are present on the friction surface. Thus, there is a problem that the frictional heat rises and the surface is damaged.

Finally, in the conventional gear module, one or more contact points may be generated according to the surface roughness of the internal gear 12 ', and friction generated at each contact point is different, thereby preventing rotation of the pin 120'. There is this.

Accordingly, there is a need for a gear module in which durability is improved by distributing the load of the pin and the rotational force of the pin is maximized.

The technical problem to be achieved by the present invention is to provide a gear module in which durability is improved by distributing the load of the pin and the rotational force of the pin is maximized.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the following description. There will be.

In order to achieve the above technical problem, an embodiment of the present invention has a plurality of teeth (Tooth) is formed on the outer circumferential surface, an eccentric rotation capable of eccentric rotation, and a plurality of grooves are formed on the inner circumferential surface, each of the grooves are connected to the external gear It includes an internal gear in which the pin is arranged, the groove and the pin are in contact at two contact points, and have a first radius of curvature greater than the radius of curvature of the pin and a first arc made of a first arc contacting any one contact point and The second curvature radius of the fin has a second radius of curvature larger than the radius of curvature of the fin, and a second overlapping portion made of a second arc contacting another contact point is formed by depression, and the first radius of curvature and the second radius of curvature are respectively. It provides a gear module that is connected to the contact point past the center point of the pin and has the same length to each other.

)은 외접기어와 핀의 유효 접촉범위의 각 경계점과 핀의 중심점을 연결한 두 개의 직선이 이루는 각(

)보다 크거나 같을 수 있다.In one embodiment of the present invention, the angle formed by two straight lines connecting the contact point and the center point of the pin (

) Is the angle formed by two straight lines connecting each boundary point of the effective contact range of the external gear and the pin and the center point of the pin.

).

In one embodiment of the present invention, depending on the size of the first radius of curvature and the second radius of curvature, the groove may be curved or straight.

In one embodiment of the present invention, due to the formation of the groove, a space is formed between the pin and the groove, and a lubricant can be accommodated in the space.

)은 사용자에 의해 선정된 접촉점에 의해 결정될 수 있다.In one embodiment of the present invention, the angle formed by two straight lines connecting each contact point and the center point of the pin (

) May be determined by a contact point selected by the user.

According to an embodiment of the present invention, it is possible to provide a gear module in which the pin and the internal gear contact at two points. Because the pin and the internal gear contact at two points, the load of the pin can be distributed at two points at a certain position regardless of the direction of the load acting on the external gear, and a lubricant film can be formed between the pin and the internal gear. , By preventing damage to the internal gear, the performance of the reducer can be improved when applied as a reducer.

It should be understood that the effects of the present invention are not limited to the above-described effects, and include all effects that can be deduced from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a view showing a portion of a conventional gear module excerpted.
2 is a plan view of a gear module according to an embodiment of the present invention.
FIG. 3 is a perspective view of the gear module illustrated in FIG. 2 partially cut away.
FIG. 4 is a view excerpting a portion of the gear module shown in FIG. 2.
FIG. 5 is a view showing a shape of a groove according to sizes of the first and second curvature radii shown in FIG. 4.
6 is a perspective view of a reducer to which a gear module according to an embodiment of the present invention is applied.
7 is an exploded view of a reduction gear to which a gear module according to an embodiment of the present invention is applied.

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be implemented in various different forms, and thus is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is "connected (connected, contacted, coupled)" to another part, this is not only when it is "directly connected", but also "indirectly" with another member in between. "It includes the case where it is. Also, when a part is said to “include” a certain component, this means that other components may be further provided instead of excluding the other component unless otherwise stated.

The terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “include” or “have” are intended to indicate that there are features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

2 is a plan view of a gear module 10 according to an embodiment of the present invention, and FIG. 3 is a perspective view of a gear module 10 according to an embodiment of the present invention in which a part is restrained.

The gear module 10 according to an embodiment of the present invention may include an external gear 11 and an internal gear 12. At this time, the external gear 11 may be inserted into a through hole formed in the center of the internal gear 12.

The circumferential gear 11 is a disk-shaped gear having a plurality of teeth formed on an outer circumferential surface and a through hole 110 at the center, and a pair of gears of the same size may be eccentrically disposed.

That is, the circumferential gear 11 is rotatably fixed to the first eccentric (22, see FIG. 7) spaced a predetermined distance in the first direction based on the rotation axis, is connected to the pin 120, and decelerates by a difference in dimensions. The first plate gear 111 and the second plate gear fixedly rotatably fixed to the second eccentric body 23 (see FIG. 7) spaced apart at a predetermined distance in a second direction opposite to the first direction based on the rotating shaft 112). At this time, the teeth of the first plate gear 111 and the second plate gear 112 may be formed of a trochoidal tooth shape, an epitrophoid tooth shape, an arc tooth shape, or the like.

The internal gear 12 is formed with a through hole through which the external gear 11 can be inserted, and a plurality of grooves 121 may be formed on the inner circumferential surface, and the pins 120 connected to the external gear 11 may be formed in each groove 121. ) May be combined. At this time, the groove 121 of the internal gear 12 may be in contact with the pin 120 at two contact points. In addition, the internal gear 12 and the pin 120 may be integrally formed.

The pin 120 may be provided with one more than the tooth of the external gear 11. Due to this, each rotation of the circumferential gear 11 is rotated by the number of teeth difference with respect to the internal gear 12 every rotation due to the number of teeth. For example, when the number of teeth of the external gear 11 is N and the number of pins 120 is N + 1, the external gear 11 is decelerated and rotated at a reduction ratio of 1 / N compared to the number of input revolutions.

Hereinafter, the groove 121 of the internal gear 12 will be described in more detail with reference to FIG. 4. FIG. 4 is a view excerpting a part of the gear module 10 shown in FIG. 2.

)보다 큰 제1곡률반경(

)을 가지며 어느 하나의 접촉점(

)과 접촉하는 제1원호로 이루어진 제1부채꼴(

)과, 핀의 곡률반경(

)보다 큰 제2곡률반경(

)을 가지며 다른 하나의 접촉점(

)과 접촉하는 제2원호로 이루어진 제2부채꼴(

)이 서로 중첩되는 부분이 함몰되어 형성될 수 있다. 이때, 제1곡률반경(

)은 핀의 중심점(

)을 지나 접촉점(

)과 연결될 수 있고, 제2곡률반경(

)은 핀의 중심점(

)을 지나 접촉점(

)과 연결될 수 있다. 또한, 제1곡률반경(

)과 제2곡률반경(

)은 서로 동일한 크기를 가질 수 있다.The groove 121 is the radius of curvature of the pin (

), The first radius of curvature greater than (

) And any one contact point (

), The first fan of the first arc (

) And the radius of curvature of the pin (

), The second radius of curvature greater than (

) And the other contact point (

A second fan made of a second arc in contact with)

) May overlap each other and may be formed. At this time, the first radius of curvature (

) Is the center point of the pin (

Past the contact point ()

), And the second radius of curvature (

) Is the center point of the pin (

Past the contact point ()

). Also, the first radius of curvature (

) And the second radius of curvature (

) May have the same size as each other.

)과 제2곡률반경(

)은 핀의 곡률반경(

)과 같거나 클 수 있다. 제1곡률반경(

)과 제2곡률반경(

)이 핀의 곡률반경(

)과 같은 경우에 홈(121)은 반원형의 곡선 형상이 되고, 제1곡률반경(

)과 제2곡률반경(

)이 핀의 곡률반경(

)보다 큰 경우에 홈(121)은 고딕 아크 형상이 되며, 제1곡률반경(

)과 제2곡률반경(

)이 핀의 곡률반경(

) 보다 무한히 커질 경우에 홈은 직선 형상이 될 수 있다. 즉, 홈(121)은 곡선 또는 직선 형태로 형성될 수 있다. (도 5 참조)Here, the first radius of curvature (

) And the second radius of curvature (

) Is the radius of curvature of the pin (

). 1st radius of curvature (

) And the second radius of curvature (

) The radius of curvature of this pin (

), The groove 121 becomes a semicircular curved shape, and the first radius of curvature (

) And the second radius of curvature (

) The radius of curvature of this pin (

), The groove 121 becomes a Gothic arc shape, and the first radius of curvature (

) And the second radius of curvature (

) The radius of curvature of this pin (

) If it becomes infinitely larger than that, the groove may have a straight shape. That is, the groove 121 may be formed in a curved or straight form. (See Figure 5)

,

)과 핀의 중심점(

)을 연결한 두 개의 직선이 이루는 각(

)이 외접기어(11)가 1회전하는 동안 핀(120)과 유효한 접촉이 유지되는 유효접촉범위의 각 경계점과 핀의 중심점(

)을 연결한 두 개의 직선이 이루는 각(

)보다 크거나 같을 수 있다.In addition, the gear module 10 has each contact point (

,

) And the center point of the pin (

) Is the angle formed by two straight lines connecting (

) Each boundary point of the effective contact range and the center point of the pin (in which the effective contact with the pin 120 is maintained while the external gear 11 is rotated one revolution (

) Is the angle formed by two straight lines connecting (

).

,

)은 특정한 지점이 아니라, 상술한 조건을 만족하는 복수의 점 중 어느 하나일 수 있다. 다시 말해, 사용자가 직접 접촉점을 선정할 수 있다.Meanwhile, in the present invention, each contact point (

,

) Is not a specific point, but may be any one of a plurality of points satisfying the above-described condition. In other words, the user can directly select the contact point.

Due to these geometric features, the present invention can improve durability by distributing the load of the pin 120, and the pin 120 and the groove 121 are in line contact at a certain position, so that the influence of surface roughness is less. Can receive In addition, the present invention can prevent the load or line segment that is prevented from rotating due to incomplete contact between the pin 120 and the groove 121.

Meanwhile, in the gear module 10, the groove 121 is formed as described above, so that the space 122 may be formed between the groove 121 and the pin 120. At this time, the space portion 122 is accommodated with a lubricant (Lubricant) to reduce the frictional force and friction heat, a lubricant film may be formed. Therefore, the present invention can reduce the incidence of surface damage due to frictional heat, and fine particles generated by abrasion can be discharged to the outside through the space portion 122.

6 is a perspective view of a reduction gear to which a gear module according to an embodiment of the present invention is applied, and FIG. 7 is an exploded view of a reduction gear to which a gear module according to an embodiment of the present invention is applied.

The reducer 1 is a device for controlling the rotational speed, an input unit 20 having an input shaft 21 for receiving power, a gear module 10 for reducing the input power by a reduction ratio, and an output shaft for outputting the reduced power ( 31) may include a housing 40 for receiving the output unit 30 and the input unit 20, the gear module 10 and the output unit 30 is formed. At this time, the input shaft 21 may be a rotating shaft of a power generator (not shown), or may be directly connected to the rotating shaft. In addition, although not shown in the drawings of the present invention, the input unit 20 may be formed in a form that meshes with the gears of the rotating shaft.

At this time, the input unit 20 is coupled to the input shaft 21 and the input shaft 21 and is coupled to the first eccentric body 22 and the input shaft 21 biased by a predetermined amount in the first direction from the center of the input shaft 21, and the input shaft ( 21) may include a second eccentric body 23 biased by a predetermined amount in the second direction opposite to the first direction from the center.

Briefly explaining the principle that the reduction gear 1 decelerates, when the input shaft 21 receives power and rotates, the external gear 11 is rotated by the eccentric bodies 22 and 23 with the rotation direction of the input shaft 21. It will rotate eccentrically in the opposite direction, and may be sequentially engaged with the pin 120 coupled to the internal gear 12. At this time, when the input shaft 21 is rotated once, the circumferential gear may be moved from the origin less by the difference between the number of teeth and pins, and may be decelerated.

7 shows the internal gear 12 and the housing 40 as separate components, but may be implemented as one component. That is, a groove is formed on the inner circumferential surface of the housing 40, and a pin may be disposed in the groove.

On the other hand, by reversing the above-described input unit 20 and output unit 30, it is also possible to configure a speed increaser.

The above description of the present invention is for illustration only, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be.

Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be interpreted to be included in the scope of the present invention.

1: reducer
10: gear module
20: input unit
30: output unit
40: housing

Claims (5)

A gear module comprising a plurality of teeth formed on the outer circumferential surface, an external gear capable of eccentric rotation, a plurality of grooves formed on the inner circumferential surface, and pins connected to the external gear for each groove In,
The groove and the pin are contacted at two contact points,
The groove has a first curvature having a first radius of curvature greater than the radius of curvature of the fin and a first arc made of a first arc contacting any one contact point and a second radius of curvature greater than the radius of curvature of the pin. The second overlapping part of the second arc made of the second arc contacting the contact point is formed by depression,
The first radius of curvature and the second radius of curvature, respectively, pass through the center point of the pin and are connected to the contact point, and have the same size as each other,
The angle formed by two straight lines connecting the contact point and the center point of the pin (

) Is the angle formed by two straight lines connecting each boundary point of the effective contact range of the external gear and the pin and the center point of the pin.

A gear module having a two-point contact internal gear, characterized in that it is greater than or equal to.
delete According to claim 1,
The groove is characterized in that it is formed in a curved or straight form, a gear module having a two-point contact internal gear.
According to claim 1,
Due to the formation of the groove, a space is formed between the pin and the groove,
The space portion, characterized in that the lubricant is accommodated, a gear module having a two-point contact internal gear.
According to claim 1,
The angle formed by two straight lines connecting the contact point and the center point of the pin (

) Is a gear module having a two-point contact internal gear, characterized in that it is determined by a contact point selected by the user.

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